A nitrocellulose/cotton fiber hybrid composite membrane for paper-based biosensor

Area of Science:

• Materials Science
• Biotechnology
• Analytical Chemistry

Background:

• Traditional nitrocellulose membranes for biosensors are often complex, expensive, and environmentally concerning.
• Existing technologies face limitations in scalability and performance for point-of-care testing (POCT).

Purpose of the Study:

• To develop a simple, cost-effective, and scalable method for fabricating nitrocellulose/cotton fiber (NC/CF) composite membranes.
• To evaluate the suitability of NC/CF composite membranes for paper-based biosensors in POCT.

Main Methods:

• NC/CF composite membranes were fabricated using papermaking technology in 15 minutes.
• Characterization included pore size, flow rate, mechanical strength (dry and wet), contact angle, and protein adsorption capacity.
• Performance was assessed using lateral flow assays (LFAs) to determine the limit of detection (LOD).

Main Results:

• The NC/CF composite membranes exhibited a small pore size (3.59 ± 0.19 μm) and low flow rate (156 ± 55 s/40 mm).
• High dry strength (up to 4.04 MPa) and wet strength (up to 0.13 MPa) were observed, along with adjustable hydrophilic-hydrophobic properties (contact angles 29° to 82.8°).
• Excellent protein adsorption capacity (up to 91.92 ± 0.07 μg) and an LOD of 1 nM in LFAs, comparable to commercial membranes, were achieved.

Conclusions:

• The developed NC/CF composite membrane is a promising, scalable, and cost-effective material for paper-based biosensors.
• Its favorable properties make it suitable for point-of-care testing applications.
• This technology offers an alternative to current complex and expensive biosensor fabrication methods.